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A342444 a(n) is the smallest number of consecutive primes that are necessary to add to obtain the largest prime = A342443(n) < 10^n.

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%I A342444 #31 Dec 15 2024 21:01:52
%S A342444 2,3,5,9,5,29,281,1575,599,7,17,3,6449,2725361,163315
%N A342444 a(n) is the smallest number of consecutive primes that are necessary to add to obtain the largest prime = A342443(n) < 10^n.
%C A342444 There are at least two consecutive primes in each sum.
%C A342444 The corresponding largest primes obtained are in A342443, and the first primes of these a(n) consecutive primes are in A342454.
%e A342444 A342443(1) = 5 = 2 + 3, hence a(1) = 2.
%e A342444 A342443(2) = 97 = 29 + 31 + 37, hence a(2) = 3.
%e A342444 From _Jon E. Schoenfield_, Mar 14 2021: (Start)
%e A342444                                                     a(n) =
%e A342444               sum of consecutive primes           number of
%e A342444       -----------------------------------------  consecutive
%e A342444    n   A342454(n)   +   ...    =    A342443(n)      primes
%e A342444   --  -----------------------------------------  -----------
%e A342444    1             2  +  3       =              5          2
%e A342444    2            29  + 31 + 37  =             97          3
%e A342444    3           191  +   ...    =            991          5
%e A342444    4          1087  +   ...    =           9949          9
%e A342444    5         19979  +   ...    =          99971          5
%e A342444    6         34337  +   ...    =         999983         29
%e A342444    7         34129  +   ...    =        9999991        281
%e A342444    8         54829  +   ...    =       99999989       1575
%e A342444    9       1665437  +   ...    =      999999937        599
%e A342444   10    1428571363  +   ...    =     9999999943          7
%e A342444   11    5882352691  +   ...    =    99999999977         17
%e A342444   12  333333333299  +   ...    =   999999999989          3
%e A342444   13    1550560001  +   ...    =  9999999999763       6449
%e A342444   14      13384757  +   ...    = 99999999999959    2725361
%e A342444 (End)
%Y A342444 Cf. A067377, A342439, A342440, A342443, A342453, A342454.
%K A342444 nonn,more
%O A342444 1,1
%A A342444 _Bernard Schott_, Mar 12 2021
%E A342444 a(6)-a(9) from _Jinyuan Wang_, Mar 13 2021
%E A342444 a(10) from _David A. Corneth_, Mar 13 2021
%E A342444 a(11)-a(14) from _Jon E. Schoenfield_, Mar 14 2021
%E A342444 a(15) from _Max Alekseyev_, Dec 11 2024